Tilting the bucket down is not a good test of downward power. Without a bucket, i can lift the front of my 743 off the ground by hand.Well I played with it yesterday and ruled out the aux hydraulics. It's seems to have plenty of power down, I can lift the whole machine with the arms and curl. When I go to lift a load I hit the pedal it goes up an inch or so then stops abruptly then again and again hot or cold. Bucket auto level valve? Messed up spool? It's crazy in there cause it's a high flow with remote steer servos. The machine has 2093 hrs the isuzu has 143 hrs.
well i have a telephone pole burried in the yard so i hook the teeth into it and it wouldnt curl. on to dirt, with the buket half to three quarters full of dirt it wont lift or curl! i bought it from my mom and step dad for cheap because of the hydro problem it has bucket positioning, and that is what he said was the problem. it worked perfect then a month ago after using a post hole digger it started doing this. he went out and got a brand new jd ct332, and sold bobcat to me. i can get a pressure gauge or cobble something up. it also has an internal leak on the tilt cylynder( it slowly bleeds down) i dont know if that has any bearing on what it is doing? thanks Nick ps i changed my avatar i think it should be my ridon lawnmower now not a political oneTilting the bucket down is not a good test of downward power. Without a bucket, i can lift the front of my 743 off the ground by hand.
Does it have bucket positioning? Can you hook the bucket into a load and curl up? does it have any power there?
Just trying to isolate the lift and tilt.
If you have access to a 3,000 psi gauge, hook it up to the aux couplers and see what pressure you get. It should be around 2,500 PSI
Aux hydraulics stuck on? Check your hyd pressure with a gauge. You may need a new hyd pump.well i have a telephone pole burried in the yard so i hook the teeth into it and it wouldnt curl. on to dirt, with the buket half to three quarters full of dirt it wont lift or curl! i bought it from my mom and step dad for cheap because of the hydro problem it has bucket positioning, and that is what he said was the problem. it worked perfect then a month ago after using a post hole digger it started doing this. he went out and got a brand new jd ct332, and sold bobcat to me. i can get a pressure gauge or cobble something up. it also has an internal leak on the tilt cylynder( it slowly bleeds down) i dont know if that has any bearing on what it is doing? thanks Nick ps i changed my avatar i think it should be my ridon lawnmower now not a political one
If you have a hose handy make a loop and put it on the auxillary fittings and see if that helps at all. if you have solenoid controlled aux may be crud in stuck in one. especially if your tilt cylinder leaks down, could be part of the seal is gone into the system. this is just from a experience with a 853 though.Aux hydraulics stuck on? Check your hyd pressure with a gauge. You may need a new hyd pump.
well i cant wait to get home! i think im the only person sitting in the office right now and the day after Christmas no less! when i finally get off i will try everones suggestions. thanks a bunch! i will keep yall posted with the results. thanks again NickIf you have a hose handy make a loop and put it on the auxillary fittings and see if that helps at all. if you have solenoid controlled aux may be crud in stuck in one. especially if your tilt cylinder leaks down, could be part of the seal is gone into the system. this is just from a experience with a 853 though.
@Jerry, well I ran down quick connects for the aux from the seller made a loop, and it didn't really seem to help, cobbled up a pressure gauge by brazing a few fittings together, then found out the gauges bezel screws had come out so it didn't work! Just my luck! So no reading today. I am starting to thing the pump is bad, because at op temp it won't do anything but drive, and good too. I'm hoping it's just gunkus in something, but I don't know. Thanks I'll keep y'all posted. Thanks againwell i cant wait to get home! i think im the only person sitting in the office right now and the day after Christmas no less! when i finally get off i will try everones suggestions. thanks a bunch! i will keep yall posted with the results. thanks again Nick
With nothing on the aux couplers and the machine at just above idle try the aux switch. It should make the engine really labor and you may hear a hiss as the relief opens.@Jerry, well I ran down quick connects for the aux from the seller made a loop, and it didn't really seem to help, cobbled up a pressure gauge by brazing a few fittings together, then found out the gauges bezel screws had come out so it didn't work! Just my luck! So no reading today. I am starting to thing the pump is bad, because at op temp it won't do anything but drive, and good too. I'm hoping it's just gunkus in something, but I don't know. Thanks I'll keep y'all posted. Thanks again
I tried that, no labour or hiss. The pressure out of the aux is 1500 psi that sucks. I have a dumb question tho, when I went to pull the main relief there is a hose on the back of it is that normal? The book dosnt show that.With nothing on the aux couplers and the machine at just above idle try the aux switch. It should make the engine really labor and you may hear a hiss as the relief opens.
What size is the hose, 1500 psi is low,needs to be around 2250, what did the o rings on the relief look like, what does the hydraulic filter look like when you pour oil from the can on a piece of white paper, are there any steel or aluminun particles ?I tried that, no labour or hiss. The pressure out of the aux is 1500 psi that sucks. I have a dumb question tho, when I went to pull the main relief there is a hose on the back of it is that normal? The book dosnt show that.
sorry its been a few days the hose on the back of the relief is a 1/2" i guess i used a 15/16" wrench to get it off yesterday. its been alittle slow going, my 10 month old son liles to wake up from his nap at 430 so i only have about an hour a day to work on it. i also got half of the main relief out it has a little plunger on it there was a lttle gunk on that part. im going to have to pull the lift detent to be able to get a socket on to get the rest of it out. i also pulled the port relief and it appered to be fine. The thing about that hose is that i had the bright idea yesterday that with the relief in half that starting it would blow the gunk out. well we all know how that ended apperently that hose that is on the back supplies pressure. I will check the filter on paper today and post back.ThanksWhat size is the hose, 1500 psi is low,needs to be around 2250, what did the o rings on the relief look like, what does the hydraulic filter look like when you pour oil from the can on a piece of white paper, are there any steel or aluminun particles ?
Happy new year! Well I pulled the rest of the reliefand the o rings were shot they were in pieces! Well I put on new ones and know it's worse! I think the front one was to small. To make matters worse it was Islamic in the yard, and it just died the battery is fine but the key and idiot lights don't work, I can jump the starter with I screwdriver and it cranks fine just won't start. I think it's the ignition fuse but it's not blown so I'm going to put a blade fuse holder in it's place. On a better note I fixed all the leaks! You can park it on white carpet and not worry. Thanks again y'all have been so much help.sorry its been a few days the hose on the back of the relief is a 1/2" i guess i used a 15/16" wrench to get it off yesterday. its been alittle slow going, my 10 month old son liles to wake up from his nap at 430 so i only have about an hour a day to work on it. i also got half of the main relief out it has a little plunger on it there was a lttle gunk on that part. im going to have to pull the lift detent to be able to get a socket on to get the rest of it out. i also pulled the port relief and it appered to be fine. The thing about that hose is that i had the bright idea yesterday that with the relief in half that starting it would blow the gunk out. well we all know how that ended apperently that hose that is on the back supplies pressure. I will check the filter on paper today and post back.Thanks
Not Islamic, idling in the yard damn iPhone autocorrect!Happy new year! Well I pulled the rest of the reliefand the o rings were shot they were in pieces! Well I put on new ones and know it's worse! I think the front one was to small. To make matters worse it was Islamic in the yard, and it just died the battery is fine but the key and idiot lights don't work, I can jump the starter with I screwdriver and it cranks fine just won't start. I think it's the ignition fuse but it's not blown so I'm going to put a blade fuse holder in it's place. On a better note I fixed all the leaks! You can park it on white carpet and not worry. Thanks again y'all have been so much help.
I am having the exact same issue. My arms will not lift and no up-pressure with the bucket. I have an 843 with High Flow. Did you have to remove the valve completely or were you able to replace the main relief valve without removing everything?Thanks everyone for this awsome forum,installed my brand new main relief today, the machine is brand-new almost! Wow it gets it! It's my first Bobcat, but definitely not my last! Thanks again, Nick
